Portion of frame for respiratory mask



FIG. 1 is a front perspective view of a portion of a frame for a respiratory mask according to our design;

FIG. 2 is a front view thereof; and,

FIG. 3 is a bottom view thereof.

The dashed lines shown in FIGS. 1–3 disclose unclaimed subject matter, are for environmental purposes only, and thus form no part of the claimed design. 

The ornamental design for a portion of frame for respiratory mask, as shown. 